已知5x-2y=9,4x+3y=6,求27x+3y的值

已知x^3+xy^2+x+x^2y+y^3+y=0,求5x-6y/3x+4y的值. 已知x.x+y.y-6x-8y+25=0,求3x.x+5y的值 1.已知:x-2y=3,求[(3x+2y)(3x-2y)-(x+2y)(5x-2y)]除4x 的值 已知x-2y=2011,求[(3x+2y)(3x-2y)-(x+2y)(5x-2y)]÷4x的值. 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 已知2x-y/x+2y=3,求2(2x-y)/x+2y-9(x+2y)/2x-y+3的值. 已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y/2x-y的值 已知X.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值 已知x^2-y^2=27,x-y=3,求y/x的值 已知3x-2y/x+y=5/3求x；y的值 已知4x-2y=0,求x-y/3x+2y的值 已知3x-4y/2x+y=1/2 求x/y的值